Zoom lens and image-pickup apparatus

Abstract

A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and a rear unit including a plurality of lens units. A distance between adjacent lens units changes during zooming. An aperture stop is arranged on an image side of the first lens unit. An image stabilizing unit Ls comprising at least part of the second lens unit moves in a direction perpendicular to an optical axis during blurring correction. The predetermined conditional expressions are satisfied.

What is claimed is: 
     
       1. A zoom lens comprising:
 in order from an object side to an image side, 
 a first lens unit having a negative refractive power; 
 a second lens unit having a positive refractive power; and 
 a rear unit including a plurality of lens units, 
 wherein a distance between adjacent lens units changes during zooming, 
 wherein an image stabilizing unit Ls comprising at least part of the second lens unit moves in a direction perpendicular to an optical axis during blurring correction, 
 wherein the image stabilizing unit Ls is disposed on a most object side of the second lens unit, 
 wherein an aperture stop is arranged on a position adjacent to an image side of the image stabilizing unit Ls, 
 wherein the zoom lens comprises a lens unit for focusing disposed on an image side of the aperture stop, 
 wherein the lens unit for focusing moves to the image side when focusing from infinity to a closest distance, and 
 wherein the following conditions are satisfied:
   1.30< f   Ls   /f   W <10.00 
   2.00< T   Exp   /f   W <5.00 
 
 
       where f Ls  represents a focal length of the image stabilizing unit Ls, T Exp  represents a distance between an exit pupil and an image surface of the zoom lens at a wide angle end, and f w  represents a focal length of the zoom lens at the wide angle end. 
     
     
       2. The zoom lens according to  claim 1 ,
 wherein the following condition is satisfied:
   0.30< T   lsmin   /f   w <1.00 
 
 
       where T lsmin  represents a minimum value of a distance between the first lens unit and the aperture stop at an arbitrary zoom position from the wide angle end to a telephoto end. 
     
     
       3. The zoom lens according to  claim 1 , wherein the image stabilizing unit Ls consists of a positive lens. 
     
     
       4. The zoom lens according to  claim 1 , wherein the following condition is satisfied:
     BF   W   /f   W <1.6 
 
       where BF W  represents a back focus at the wide angle end. 
     
     
       5. The zoom lens according to  claim 1 , wherein the rear unit, in order from the object side to the image side, comprises a third lens unit having a negative refractive power and a fourth lens unit having a positive refractive power. 
     
     
       6. The zoom lens according to  claim 5 , wherein the third lens unit moves in the optical axis direction during focusing. 
     
     
       7. The zoom lens according to  claim 1 , wherein the rear unit, in order from the object side to the image side, comprises a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power and a fifth lens unit having a positive refractive power. 
     
     
       8. The zoom lens according to  claim 7 , wherein the third lens unit moves in the optical axis direction during focusing. 
     
     
       9. The zoom lens according to  claim 1 , wherein the zoom lens forms an image on a photoelectric conversion element. 
     
     
       10. An image pickup apparatus comprising:
 a zoom lens; and 
 a photoelectric conversion element configured to receive an image formed by the zoom lens, 
 wherein the zoom lens comprises:
 in order from an object side to an image side, 
 a first lens unit having a negative refractive power; 
 a second lens unit having a positive refractive power; and 
 a rear unit including a plurality of lens units, 
 wherein a distance between adjacent lens units changes during zooming, 
 wherein an image stabilizing unit Ls comprising at least part of the second lens unit moves in a direction perpendicular to an optical axis during blurring correction, 
 wherein the image stabilizing unit Ls is disposed on a most object side of the second lens unit, 
 wherein an aperture stop is arranged on a position adjacent to an image side of the image stabilizing unit Ls, 
 wherein the zoom lens comprises a lens unit for focusing disposed on an image side of the aperture stop, 
 wherein the lens unit for focusing moves to the image side when focusing from infinity to a closest distance, and 
 wherein the following conditions are satisfied:
   1.30< f   Ls   /f   W <10.00 
   2.00< T   Exp   /f   W <5.00 
 
 
 where f Ls  represents a focal length of the image stabilizing unit Ls, T Exp  represents a distance between an exit pupil and an image surface of the zoom lens at a wide angle end, and f w  represents a focal length of the zoom lens at the wide angle end. 
 
     
     
       11. The image pickup apparatus according to  claim 10 , wherein the following condition is satisfied:
     BF   W   /Y   max <1.8 
 
       where BF W  represents a back focus at the wide angle end, and Y max  represents a maximum image height.